Move error reporting out of the callers, into virURIParse
and virURIFormat, to get consistency.

* include/libvirt/virterror.h, src/util/virterror.c: Add VIR_FROM_URI
* src/util/viruri.c, src/util/viruri.h: Add error reporting
* src/esx/esx_driver.c, src/libvirt.c, src/libxl/libxl_driver.c,
  src/lxc/lxc_driver.c, src/openvz/openvz_driver.c,
  src/qemu/qemu_driver.c, src/qemu/qemu_migration.c,
  src/remote/remote_driver.c, src/uml/uml_driver.c,
  src/vbox/vbox_tmpl.c, src/vmx/vmx.c, src/xen/xen_driver.c,
  src/xen/xend_internal.c, tests/viruritest.c: Remove error
  reporting
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

There are several functions in domain_conf.c that remove a device
object from the domain's list of that object type, but don't free the
object or return it to the caller to free. In many cases this isn't a
problem because the caller already had a pointer to the object and
frees it afterward, but in several cases the removed object was just
left floating around with no references to it.

In particular, the function qemuDomainDetachDeviceConfig() calls
functions to locate and remove net (virDomainNetRemoveByMac), disk
(virDomainDiskRemoveByName()), and lease (virDomainLeaseRemove())
devices, but neither it nor its caller qemuDomainModifyDeviceConfig()
ever obtain a pointer to the device being removed, much less free it.

This patch modifies the following "remove" functions to return a
pointer to the device object being removed from the domain device
arrays, to give the caller the option of freeing the device object
using that pointer if needed. In places where the object was
previously leaked, it is now freed:

  virDomainDiskRemove
  virDomainDiskRemoveByName
  virDomainNetRemove
  virDomainNetRemoveByMac
  virDomainHostdevRemove
  virDomainLeaseRemove
  virDomainLeaseRemoveAt

The functions that had been leaking:

  libxlDomainDetachConfig - leaked a virDomainDiskDef
  qemuDomainDetachDeviceConfig - could leak a virDomainDiskDef,
                            a virDomainNetDef, or a
                            virDomainLeaseDef
  qemuDomainDetachLease   - leaked a virDomainLeaseDef

On 64-bit platforms, unsigned long and unsigned long long are
identical, so we don't have to worry about overflow checks.
On 32-bit platforms, anywhere we narrow unsigned long long back
to unsigned long, we have to worry about overflow; it's easier
to do this in one place by having most of the code use the same
or wider types, and only doing the narrowing at the last minute.
Therefore, the memory set commands remain unsigned long, and
the memory get command now centralizes the overflow check into
libvirt.c, so that drivers don't have to repeat the work.

This also fixes a bug where xen returned the wrong value on
failure (most APIs return -1 on failure, but getMaxMemory
must return 0 on failure).

* src/driver.h (virDrvDomainGetMaxMemory): Use long long.
* src/libvirt.c (virDomainGetMaxMemory): Raise overflow.
* src/test/test_driver.c (testGetMaxMemory): Fix driver.
* src/rpc/gendispatch.pl (name_to_ProcName): Likewise.
* src/xen/xen_hypervisor.c (xenHypervisorGetMaxMemory): Likewise.
* src/xen/xen_driver.c (xenUnifiedDomainGetMaxMemory): Likewise.
* src/xen/xend_internal.c (xenDaemonDomainGetMaxMemory):
Likewise.
* src/xen/xend_internal.h (xenDaemonDomainGetMaxMemory):
Likewise.
* src/xen/xm_internal.c (xenXMDomainGetMaxMemory): Likewise.
* src/xen/xm_internal.h (xenXMDomainGetMaxMemory): Likewise.
* src/xen/xs_internal.c (xenStoreDomainGetMaxMemory): Likewise.
* src/xen/xs_internal.h (xenStoreDomainGetMaxMemory): Likewise.
* src/xenapi/xenapi_driver.c (xenapiDomainGetMaxMemory):
Likewise.
* src/esx/esx_driver.c (esxDomainGetMaxMemory): Likewise.
* src/libxl/libxl_driver.c (libxlDomainGetMaxMemory): Likewise.
* src/qemu/qemu_driver.c (qemudDomainGetMaxMemory): Likewise.
* src/lxc/lxc_driver.c (lxcDomainGetMaxMemory): Likewise.
* src/uml/uml_driver.c (umlDomainGetMaxMemory): Likewise.

This call to virDomainDeviceDefParse is both unnecessary (since
it will again be called at the top of the immediately following if(),
and if not there, then at the top of the if following that), but it
also creates a leak of one virDomainDeviceDef and one [whatever type
of device the DeviceDef is pointing to; probably a virDomainDiskDef]
in the case that the function has been called with
VIR_DOMAIN_DEVICE_MODIFY_CONFIG (the second parse will overwrite the
devicedef that was just created).

Function xmlParseURI does not remove square brackets around IPv6
address when parsing. One of the solutions is making wrappers around
functions working with xmlURI*. This assures that uri->server will be
always properly assigned and it doesn't have to be changed when used
on some new place in the code.
For this purpose, functions virParseURI and virSaveURI were
added. These function are wrappers around xmlParseURI and xmlSaveUri
respectively.
Also there is one new syntax check function to prohibit these functions
anywhere else.

File changes:
 - src/util/viruri.h        -- declaration
 - src/util/viruri.c        -- definition
 - src/libvirt_private.syms -- symbol export
 - src/Makefile.am          -- added source and header files
 - cfg.mk                   -- added sc_prohibit_xmlURI
 - all others               -- ID name and include fixes

virFileOpenAs previously would only try opening a file as the current
user, or as a different user, but wouldn't try both methods in a
single call. This made it cumbersome to use as a replacement for
open(2). Additionally, it had a lot of historical baggage that led to
it being difficult to understand.

This patch refactors virFileOpenAs in the following ways:

* reorganize the code so that everything dealing with both the parent
  and child sides of the "fork+setuid+setgid+open" method are in a
  separate function. This makes the public function easier to understand.

* Allow a single call to virFileOpenAs() to first attempt the open as
  the current user, and if that fails to automatically re-try after
  doing fork+setuid (if deemed appropriate, i.e. errno indicates it
  would now be successful, and the file is on a networkFS). This makes
  it possible (in many, but possibly not all, cases) to drop-in
  virFileOpenAs() as a replacement for open(2).

  (NB: currently qemuOpenFile() calls virFileOpenAs() twice, once
  without forking, then again with forking. That unfortunately can't
  be changed without at least some discussion of the ramifications,
  because the requested file permissions are different in each case,
  which is something that a single call to virFileOpenAs() can't deal
  with.)

* Add a flag so that any fchown() of the file to a different uid:gid
  is explicitly requested when the function is called, rather than it
  being implied by the presence of the O_CREAT flag. This just makes
  for less subtle surprises to consumers. (Commit
  b1643dc1 added the check for O_CREAT
  before forcing ownership. This patch just makes that restriction
  more explicit.)

* If either the uid or gid is specified as "-1", virFileOpenAs will
  interpret this to mean "the current [gu]id".

All current consumers of virFileOpenAs should retain their present
behavior (after a few minor changes to their setup code and
arguments).

Add a new API virDomainShutdownFlags and define:

    VIR_DOMAIN_SHUTDOWN_DEFAULT        = 0,
    VIR_DOMAIN_SHUTDOWN_ACPI_POWER_BTN = (1 << 0),
    VIR_DOMAIN_SHUTDOWN_GUEST_AGENT    = (1 << 1),

Also define some flags for the reboot API

    VIR_DOMAIN_REBOOT_DEFAULT        = 0,
    VIR_DOMAIN_REBOOT_ACPI_POWER_BTN = (1 << 0),
    VIR_DOMAIN_REBOOT_GUEST_AGENT    = (1 << 1),

Although these two APIs currently have the same flags, using
separate enums allows them to expand separately in the future.

Add stub impls of the new API for all existing drivers

Reusing common code makes things smaller; it also buys us some
additional safety, such as now rejecting duplicate parameters
during a set operation.

* src/qemu/qemu_driver.c (qemuDomainSetBlkioParameters)
(qemuDomainSetMemoryParameters, qemuDomainSetNumaParameters)
(qemuSetSchedulerParametersFlags)
(qemuDomainSetInterfaceParameters, qemuDomainSetBlockIoTune)
(qemuDomainGetBlkioParameters, qemuDomainGetMemoryParameters)
(qemuDomainGetNumaParameters, qemuGetSchedulerParametersFlags)
(qemuDomainBlockStatsFlags, qemuDomainGetInterfaceParameters)
(qemuDomainGetBlockIoTune): Use new helpers.
* src/esx/esx_driver.c (esxDomainSetSchedulerParametersFlags)
(esxDomainSetMemoryParameters)
(esxDomainGetSchedulerParametersFlags)
(esxDomainGetMemoryParameters): Likewise.
* src/libxl/libxl_driver.c
(libxlDomainSetSchedulerParametersFlags)
(libxlDomainGetSchedulerParametersFlags): Likewise.
* src/lxc/lxc_driver.c (lxcDomainSetMemoryParameters)
(lxcSetSchedulerParametersFlags, lxcDomainSetBlkioParameters)
(lxcDomainGetMemoryParameters, lxcGetSchedulerParametersFlags)
(lxcDomainGetBlkioParameters): Likewise.
* src/test/test_driver.c (testDomainSetSchedulerParamsFlags)
(testDomainGetSchedulerParamsFlags): Likewise.
* src/xen/xen_hypervisor.c (xenHypervisorSetSchedulerParameters)
(xenHypervisorGetSchedulerParameters): Likewise.

The lifetime of the virDomainEventState object is tied to
the lifetime of the driver, which in stateless drivers is
tied to the lifetime of the virConnectPtr.

If we add & remove a timer when allocating/freeing the
virDomainEventState object, we can get a situation where
the timer still triggers once after virDomainEventState
has been freed. The timeout callback can't keep a ref
on the event state though, since that would be a circular
reference.

The trick is to only register the timer when a callback
is registered with the event state & remove the timer
when the callback is unregistered.

The demo for the bug is to run

  while true ; do date ; ../tools/virsh -q -c test:///default 'shutdown test; undefine test; dominfo test' ; done

prior to this fix, it will frequently hang and / or
crash, or corrupt memory

Currently all drivers using domain events need to provide a callback
for handling a timer to dispatch events in a clean stack. There is
no technical reason for dispatch to go via driver specific code. It
could trivially be dispatched directly from the domain event code,
thus removing tedious boilerplate code from all drivers

Also fix the libxl & xen drivers to pass 'true' when creating the
virDomainEventState, since they run inside the daemon & thus always
expect events to be present.

* src/conf/domain_event.c, src/conf/domain_event.h: Internalize
  dispatch of events from timer callback
* src/libxl/libxl_driver.c, src/lxc/lxc_driver.c,
  src/qemu/qemu_domain.c, src/qemu/qemu_driver.c,
  src/remote/remote_driver.c, src/test/test_driver.c,
  src/uml/uml_driver.c, src/vbox/vbox_tmpl.c,
  src/xen/xen_driver.c: Remove all timer dispatch functions

* src/libxl/libxl_driver.c, src/lxc/lxc_driver.c,
  src/qemu/qemu_driver.c, src/remote/remote_driver.c,
  src/test/test_driver.c, src/uml/uml_driver.c,
  src/vbox/vbox_tmpl.c, src/xen/xen_driver.c: Convert
  to threadsafe APIs

When registering a callback for a particular event some callers
need to know how many callbacks already exist for that event.
While it is possible to ask for a count, this is not free from
race conditions when threaded. Thus the API for registering
callbacks should return the count of callbacks. Also rename
virDomainEventStateDeregisterAny to virDomainEventStateDeregisterID

* src/conf/domain_event.c, src/conf/domain_event.h,
  src/libvirt_private.syms: Return count of callbacks when
  registering callbacks
* src/libxl/libxl_driver.c, src/libxl/libxl_driver.c,
  src/qemu/qemu_driver.c, src/remote/remote_driver.c,
  src/remote/remote_driver.c, src/uml/uml_driver.c,
  src/vbox/vbox_tmpl.c, src/xen/xen_driver.c: Update
  for change in APIs

Allow the user to call with nparams too small, per API documentation.

* src/libxl/libxl_driver.c
(libxlDomainGetSchedulerParametersFlags): Allow fewer than max.

Document the parameter names that will be used by
virDomain{Get,Set}SchedulerParameters{,Flags}, rather than
hard-coding those names in each driver, to match what is
done with memory, blkio, and blockstats parameters.

* include/libvirt/libvirt.h.in (VIR_DOMAIN_SCHEDULER_CPU_SHARES)
(VIR_DOMAIN_SCHEDULER_VCPU_PERIOD)
(VIR_DOMAIN_SCHEDULER_VCPU_QUOTA, VIR_DOMAIN_SCHEDULER_WEIGHT)
(VIR_DOMAIN_SCHEDULER_CAP, VIR_DOMAIN_SCHEDULER_RESERVATION)
(VIR_DOMAIN_SCHEDULER_LIMIT, VIR_DOMAIN_SCHEDULER_SHARES): New
field name macros.
* src/qemu/qemu_driver.c (qemuSetSchedulerParametersFlags)
(qemuGetSchedulerParametersFlags): Use new defines.
* src/test/test_driver.c (testDomainGetSchedulerParamsFlags)
(testDomainSetSchedulerParamsFlags): Likewise.
* src/xen/xen_hypervisor.c (xenHypervisorGetSchedulerParameters)
(xenHypervisorSetSchedulerParameters): Likewise.
* src/xen/xend_internal.c (xenDaemonGetSchedulerParameters)
(xenDaemonSetSchedulerParameters): Likewise.
* src/lxc/lxc_driver.c (lxcSetSchedulerParametersFlags)
(lxcGetSchedulerParametersFlags): Likewise.
* src/esx/esx_driver.c (esxDomainGetSchedulerParametersFlags)
(esxDomainSetSchedulerParametersFlags): Likewise.
* src/libxl/libxl_driver.c (libxlDomainGetSchedulerParametersFlags)
(libxlDomainSetSchedulerParametersFlags): Likewise.

Variable 'l_disk' initialized to a null pointer value, control jumps to 'case
VIR_DOMAIN_DISK_DEVICE_DISK and then taking false branch, Within the expansion
of the macro 'libxlError': Field access results in a dereference of a null
pointer (loaded from variable 'l_disk').

* src/libxl/libxl_driver.c: Field access results in a dereference of a null
  pointer (loaded from variable 'l_disk')
Signed-off-by: NAlex Jia <ajia@redhat.com>

I got confused when 'virsh domblkinfo dom disk' required the
path to a disk (which can be ambiguous, since a single file
can back multiple disks), rather than the unambiguous target
device name that I was using in disk snapshots.  So, in true
developer fashion, I went for the best of both worlds - all
interfaces that operate on a disk (aka block) now accept
either the target name or the unambiguous path to the backing
file used by the disk.

* src/conf/domain_conf.h (virDomainDiskIndexByName): Add
parameter.
(virDomainDiskPathByName): New prototype.
* src/libvirt_private.syms (domain_conf.h): Export it.
* src/conf/domain_conf.c (virDomainDiskIndexByName): Also allow
searching by path, and decide whether ambiguity is okay.
(virDomainDiskPathByName): New function.
(virDomainDiskRemoveByName, virDomainSnapshotAlignDisks): Update
callers.
* src/qemu/qemu_driver.c (qemudDomainBlockPeek)
(qemuDomainAttachDeviceConfig, qemuDomainUpdateDeviceConfig)
(qemuDomainGetBlockInfo, qemuDiskPathToAlias): Likewise.
* src/qemu/qemu_process.c (qemuProcessFindDomainDiskByPath):
Likewise.
* src/libxl/libxl_driver.c (libxlDomainAttachDeviceDiskLive)
(libxlDomainDetachDeviceDiskLive, libxlDomainAttachDeviceConfig)
(libxlDomainUpdateDeviceConfig): Likewise.
* src/uml/uml_driver.c (umlDomainBlockPeek): Likewise.
* src/xen/xend_internal.c (xenDaemonDomainBlockPeek): Likewise.
* docs/formatsnapshot.html.in: Update documentation.
* tools/virsh.pod (domblkstat, domblkinfo): Likewise.
* docs/schemas/domaincommon.rng (diskTarget): Tighten pattern on
disk targets.
* docs/schemas/domainsnapshot.rng (disksnapshot): Update to match.
* tests/domainsnapshotxml2xmlin/disk_snapshot.xml: Update test.

If the libxl driver is compiled in, then everytime libvirtd
starts up on a non-Xen Dom0 host, it logs a error message.
Since this is an expected condition, we should not log at
'error' level, only 'info'.

* src/libxl/libxl_driver.c: Lower log level for certain
  expected errors during driver init

Undefining a running domain will convert it to trasient, but keep
the domain still running.

Transient domains reject attempts to set autostart, and using
virDomainCreate to restart a domain only works on persistent
domains.  Therefore, managed save makes no sense on transient
domains, and should be rejected up front rather than creating
an otherwise unrecoverable managed save file.

Besides, transient domains imply that a lot more management is
being done by the upper layer; this includes the assumption
that the upper layer is okay managing the saved state file
created by virDomainSave, and does not need to use managed save.

* src/libvirt.c: Document that transient domains are incompatible
with managed save.
* src/qemu/qemu_driver.c (qemuDomainManagedSave): Enforce it.
* src/libxl/libxl_driver.c (libxlDomainManagedSave): Likewise.

Now that virDomainSetVcpusFlags knows about VIR_DOMAIN_AFFECT_CURRENT,
so should virDomainGetVcpusFlags.

Unfortunately, the virsh counterpart 'virsh vcpucount' has already
commandeered --current for a different meaning, so teaching virsh
to expose this in the next patch will require a bit of care.

* src/libvirt.c (virDomainGetVcpusFlags): Allow
VIR_DOMAIN_AFFECT_CURRENT.
* src/libxl/libxl_driver.c (libxlDomainGetVcpusFlags): Likewise.
* src/qemu/qemu_driver.c (qemudDomainGetVcpusFlags): Likewise.
* src/test/test_driver.c (testDomainGetVcpusFlags): Likewise.
* src/xen/xen_driver.c (xenUnifiedDomainGetVcpusFlags): Likewise.

For all hypervisors that support save and restore, the new API
now performs the same functions as the old.

VBox is excluded from this list, because its existing domainsave
is broken (there is no corresponding domainrestore, and there
is no control over the filename used in the save).  A later
patch should change vbox to use its implementation for
managedsave, and teach start to use managedsave results.

* src/libxl/libxl_driver.c (libxlDomainSave): Move guts...
(libxlDomainSaveFlags): ...to new function.
(libxlDomainRestore): Move guts...
(libxlDomainRestoreFlags): ...to new function.
* src/test/test_driver.c (testDomainSave, testDomainSaveFlags)
(testDomainRestore, testDomainRestoreFlags): Likewise.
* src/xen/xen_driver.c (xenUnifiedDomainSave)
(xenUnifiedDomainSaveFlags, xenUnifiedDomainRestore)
(xenUnifiedDomainRestoreFlags): Likewise.
* src/qemu/qemu_driver.c (qemudDomainSave, qemudDomainRestore):
Rename and move guts.
(qemuDomainSave, qemuDomainSaveFlags, qemuDomainRestore)
(qemuDomainRestoreFlags): ...here.
(qemudDomainSaveFlag): Rename...
(qemuDomainSaveInternal): ...to this, and update callers.

In preparation for a future patch adding new virFile APIs.

* src/util/files.h, src/util/files.c: Move...
* src/util/virfile.h, src/util/virfile.c: ...here, and rename
functions to virFile prefix.  Macro names are intentionally
left alone.
* *.c: All '#include "files.h"' uses changed.
* src/Makefile.am (UTIL_SOURCES): Reflect rename.
* cfg.mk (exclude_file_name_regexp--sc_prohibit_close): Likewise.
* src/libvirt_private.syms: Likewise.
* docs/hacking.html.in: Likewise.
* HACKING: Regenerate.

* src/libxl/libxl_driver.c (libxlDomainUndefineFlags): Use correct
enum value.
* src/remote_protocol-structs (remote_procedure): Likewise.

* src/libxl/libxl_driver.c: New callback for libxl_driver,
new function libxlDomainUndefineFlags, and changes libxlDomainUndefine
as a wrapper of libxlDomainUndefineFlags.

The previous patches only cleaned up ATTRIBUTE_UNUSED flags cases;
auditing the drivers found other places where flags was being used
but not validated.  In particular, domainGetXMLDesc had issues with
clients accepting a different set of flags than the common
virDomainDefFormat helper function.

* src/conf/domain_conf.c (virDomainDefFormat): Add common flag check.
* src/uml/uml_driver.c (umlDomainAttachDeviceFlags)
(umlDomainDetachDeviceFlags): Reject unknown
flags.
* src/vbox/vbox_tmpl.c (vboxDomainGetXMLDesc)
(vboxDomainAttachDeviceFlags)
(vboxDomainDetachDeviceFlags): Likewise.
* src/qemu/qemu_driver.c (qemudDomainMemoryPeek): Likewise.
(qemuDomainGetXMLDesc): Document common flag handling.
* src/libxl/libxl_driver.c (libxlDomainGetXMLDesc): Likewise.
* src/lxc/lxc_driver.c (lxcDomainGetXMLDesc): Likewise.
* src/openvz/openvz_driver.c (openvzDomainGetXMLDesc): Likewise.
* src/phyp/phyp_driver.c (phypDomainGetXMLDesc): Likewise.
* src/test/test_driver.c (testDomainGetXMLDesc): Likewise.
* src/vmware/vmware_driver.c (vmwareDomainGetXMLDesc): Likewise.
* src/xenapi/xenapi_driver.c (xenapiDomainGetXMLDesc): Likewise.

* src/libxl/libxl_driver.c (libxlOpen, libxlDomainReboot)
(libxlDomainXMLFromNative, libxlDomainXMLToNative)
(libxlDomainCreateWithFlags): Reject unknown flags.

The drivers were accepting domain configs without checking if those
were actually meant for them. For example the LXC driver happily
accepts configs with type QEMU.

Add a check for the expected domain types to the virDomainDefParse*
functions.

Now that the public APIs always use unsigned flags, the internal
driver callbacks might as well do likewise.

* src/driver.h (vrDrvOpen, virDrvDomainCoreDump)
(virDrvDomainGetXMLDesc, virDrvNetworkGetXMLDesc)
(virDrvNWFilterGetXMLDesc): Update type.
* src/remote/remote_protocol.x (remote_open_args)
(remote_domain_core_dump_args, remote_domain_get_xml_desc_args)
(remote_network_get_xml_desc_args)
(remote_nwfilter_get_xml_desc_args): Likewise.
* src/test/test_driver.c: Update clients.
* src/remote/remote_driver.c: Likewise.
* src/xen/xen_hypervisor.c: Likewise.
* src/xen/xen_hypervisor.h: Likewise.
* src/xen/xen_driver.c: Likewise.
* src/xen/xend_internal.c: Likewise.
* src/xen/xend_internal.h: Likewise.
* src/xen/xm_internal.c: Likewise.
* src/xen/xm_internal.h: Likewise.
* src/xen/xs_internal.c: Likewise.
* src/xen/xs_internal.h: Likewise.
* src/xen/xen_inotify.c: Likewise.
* src/xen/xen_inotify.h: Likewise.
* src/phyp/phyp_driver.c: Likewise.
* src/openvz/openvz_driver.c: Likewise.
* src/vmware/vmware_driver.c: Likewise.
* src/vbox/vbox_driver.c: Likewise.
* src/vbox/vbox_tmpl.c: Likewise.
* src/xenapi/xenapi_driver.c: Likewise.
* src/esx/esx_driver.c: Likewise.
* src/esx/esx_interface_driver.c: Likewise.
* src/esx/esx_network_driver.c: Likewise.
* src/esx/esx_storage_driver.c: Likewise.
* src/esx/esx_device_monitor.c: Likewise.
* src/esx/esx_secret_driver.c: Likewise.
* src/esx/esx_nwfilter_driver.c: Likewise.
* src/interface/netcf_driver.c: Likewise.
* src/nwfilter/nwfilter_driver.c: Likewise.
* src/libxl/libxl_driver.c: Likewise.
* src/qemu/qemu_driver.c: Likewise.
* src/lxc/lxc_driver.c: Likewise.
* src/uml/uml_driver.c: Likewise.
* src/network/bridge_driver.c: Likewise.
* src/secret/secret_driver.c: Likewise.
* src/storage/storage_driver.c: Likewise.
* src/node_device/node_device_hal.c: Likewise.
* src/node_device/node_device_udev.c: Likewise.
* src/remote_protocol-structs: Likewise.

Some callers expected virFileMakePath to set errno, some expected
it to return an errno value. Unify this to return 0 on success and
-1 on error. Set errno to report detailed error information.

Also optimize virFileMakePath if stat fails with an errno different
from ENOENT.

We already have a public virDomainPinVcpu, which implies that
Pin and Vcpu are treated as separate words.  Unreleased commit
e261987c introduced virDomainGetVcpupinInfo as the first public
API that used Vcpupin, although we had prior internal uses of
that spelling.  For consistency, change the spelling to be two
words everywhere, regardless of whether pin comes first or last.

* daemon/remote.c: Treat vcpu and pin as separate words.
* include/libvirt/libvirt.h.in: Likewise.
* src/conf/domain_conf.c: Likewise.
* src/conf/domain_conf.h: Likewise.
* src/driver.h: Likewise.
* src/libvirt.c: Likewise.
* src/libvirt_private.syms: Likewise.
* src/libvirt_public.syms: Likewise.
* src/libxl/libxl_driver.c: Likewise.
* src/qemu/qemu_driver.c: Likewise.
* src/remote/remote_driver.c: Likewise.
* src/xen/xend_internal.c: Likewise.
* tools/virsh.c: Likewise.
* src/remote/remote_protocol.x: Likewise.
* src/remote_protocol-structs: Likewise.
Suggested by Matthias Bolte.

Since we virEventRegisterDefaultImpl is now a public API, callers need
a way to invoke the default registered Handle and Timeout functions. We
already have general functions for these internally, so promote
them to the public API.

v2:
    Actually add APIs to libvirt.h

There were a few minor issues in commit 5b6c961e
- leak managed save path
- leak managed save fd
- functions that open an fd should also close it

Based on the equivalent qemu driver code

* src/libxl/libxl_driver.c: refactor the Start save and restore
  routines of the driver and adds the new entry points for
  managed saves handling

* src/libxl/libxl_driver.c: fix the libxlDomainGetInfo to return the
  maximum memory for running domain

Add support to set the maximum memory of the domain.
Also add support to change the memory of the current
state of the domain, which translates to a running
domain or the config of the domain.

Based on the code from the qemu driver.